Various methods of analyzing a state of a person captured in a monitoring image by using the image have been proposed. These methods are used for prevention of crimes, prevention of disasters, detection of abnormalities, and the like.
The following Patent Document 1 proposes a method in which an input image is divided into partial regions, it is determined whether or not a person is present in each partial region by using movement information of the image and texture information of the image, and a trend of the flow rate of people or an abnormal crowding is determined based on the image. The following Non-Patent Document 1 proposes a method in which movements of pixels of video scenes are measured by using a technique called optical flow, and movements of the crowd are estimated. According to FIG. 6(a) of the following Patent Document 1, a movement for circumventing a specific region is estimated.